1. Field of the Invention
The invention relates to a base element for a YIG band-pass filter or YIG oscillator.
2. Related Technology
YIG band-pass filters or YIG oscillators contain at least one YIG element, which is preferably spherical in shape and manufactured from an yttrium-iron-garnet (YIG). The resonator effect is mediated by means of coupling loops, which must be formed and arranged in such a manner that the center point of the YIG element and the center point of the bend radius of coupling loop coincide exactly.
A YIG band-pass filter with correspondingly-formed coupling loops is known, for example, from U.S. Pat. No. 4,480,238. In this context, the adjustable YIG band-pass filter provides a base element, which comprises slots for the accommodation of insulated laminas with a conductive coating on one edge, which is used as a coupling conductor. Furthermore, filter chambers are provided to accommodate the YIG elements. The laminas are fitted over the YIG elements into the slots in such a manner that the YIG elements are arranged in indentations in the edges provided with conductive coating. The YIG elements and the laminas are attached in fixed positions.
The particular disadvantage of YIG band-pass filters with wire loops as coupling elements, as known from practical experience, is that the manufacture of the YIG filter by manual bending of the coupling loops is expensive, complicated and associated with a high reject rate.